Furnace wall assemblies are generally comprised of inner and outer wall panels held in spaced apart relationship by supporting members, thereby forming a dead air space or area for insertion of insulation between said panels. Conventionally, to insure adequate support and to withstand the extreme heats often involved, said members are constructed of various metals, usually ferrous metals or alloys. However, since such metals are thermally conductive, heat loss through the furnace wall is aggravated. Efforts have been made to reduce heat transfer across the supporting members by removing portions of metal from said supports, i.e., perforation. While these techniques are somewhat effective, the removal of sufficient metal to significantly lower heat loss weakens the strength of the member.